But members of the Hopi Tribe of Arizona say the pieces should not be sold and instead should be returned to Hopi villages. They've asked U.S. officials to intervene.

Leigh J. Kuwanwisiwma, director of the Hopi Cultural Preservation Office in Kykotsmovi, Ariz., told The Times: "Sacred items like this should not have a commercial value. The bottom line is we believe they were taken illegally."

Tribal members say the sacred objects are not "masks" and that outsiders who photograph, collect or sell them are committing sacrilege, according to the Times. It adds:

"The Hopis, who number about 18,000 in northeast Arizona, regard the objects in the Paris sale, which they call Katsinam, or 'friends,' as imbued with divine spirits. ...

"The brightly colored visages and headdresses, often adorned with horsehair, sheepskin, feathers and maize, are thought to embody the spirits of warriors, animals, messengers, fire, rain and clouds, among other things. They are used today, as in the past, in many Hopi rites, like coming-of-age ceremonies and harvest rituals."

The owner of the items slated for auction hasn't been publicly identified, but the auctioneers say the pieces were legally obtained by a French collector over more than 30 years while living in the U.S.

Last week, Philip J. Breeden, cultural affairs minister for the U.S. Embassy in Paris, wrote to the Neret-Minet auction house asking it to postpone the sale. "Given the ancestry of these masks and the distance between Paris and the Hopi reservation, requesting a delay seems reasonable to allow for a complete examination of the situation," he wrote, according to the Times.

On Tuesday, the advocacy group Survival International filed a court action in Paris to try and stop the sale. A hearing is scheduled for Thursday to determine whether the sale can proceed.

And I'm Melissa Block. A Paris auction house wants to put 70 artifacts sacred to the Hopi people up for sale. The Arizona tribe says the artifacts belong on the reservation and were removed without permission. Well, tomorrow, a judge in Paris plans to hold a hearing to determine the legality of the auction. From member station KJZZ, Laurel Morales reports.

LAUREL MORALES, BYLINE: This story contains language so sensitive to the Hopi people that the tribe doesn't even want us to describe what the sacred objects are. They're called katsina friends by the Hopi. To the outside world, they're tribal masks.

ROBERT BREUNIG: Hopis do not think of these as inert objects.

MORALES: Museum of Northern Arizona director and anthropologist Robert Breunig says the Hopi think of them as living beings. When a Hopi puts one on for a ceremony, he becomes a katsina spirit.

BREUNIG: Their word is iquatzi, my friend. It is a friend. So it's a living thing. And you don't take living things and sell them. That would be like selling maybe one of your children.

MORALES: The artifacts up for sale are used in religious ceremonies in which the Hopi pray for rain, healing and protection. The tribe has contacted the White House and the U.S. State Department requesting their help. Breunig has also sent a letter to the Neret-Minet Auction House asking them to cancel the sale.

BREUNIG: Where a Westerner would see it as an artwork, the Hopis see it as something much more and something that cannot, cannot be sold in this way. It is incredibly painful for them.

MORALES: And that's why the Hopi Tribal Council recently talked to reporters. They wanted to put public pressure on the auction house. Chairman LeRoy Shingoitewa says taking these items off Hopi land is against tribal law. In essence, they're stolen.

LEROY SHINGOITEWA: Today, if I was to go downtown of Flagstaff and go into any one of the churches and take a figure of Christ or a cross or whatever and go outside and use it for a fence post, in this country, I would be prosecuted immediately. Our dilemma is that now, we're working in international waters.

MORALES: The tribe has successfully repatriated items from museums in the United States with the help of the 1990 Native American Graves Protection and Repatriation Act. While that law cannot help them outside the U.S., DePaul University law professor Patty Gerstenblith says property law might.

PATTY GERSTENBLITH: If an object is community owned, owned by a group, then an individual from that group could not necessarily - would not have the authority to sell the object without the permission of the whole group.

MORALES: For its part, the Neret-Minet Auction House says all the items were obtained legally. In fact, two earlier sales in 2003 and 2006 took place in Paris without objections. Art expert Eric Geneste works for the auction house and says they have papers proving ownership.

ERIC GENESTE: (Foreign language spoken)

MORALES: Geneste says everything was bought from galleries. The auction house has to verify everything and make sure they were legally acquired. Geneste also says no one knows how the items were originally obtained, but it was well before the Native American Graves and Repatriation Act. Some of these items date back to the 1930s. Geneste says if the U.S. State Department requested the auction's suspension from the French government, France would pay attention.

France does not recognize Hopi as a sovereign nation. Geneste suggests if people are so concerned about the issue, a corporation with deep pockets should come to the tribe's rescue, buy up all the items and return them to the Hopi people. For NPR News, I'm Laurel Morales in Flagstaff. Transcript provided by NPR, Copyright NPR.